The writing process for the majority of Metallicaâs albums have followed the same process. A large slew of guitar riffs written primarily by James Hetfield, sometimes Kirk Hammett, and rarely the bandâs bass player, (that now being bass virtuoso Robert Trujillo) are reviewed and selected.
1 Delhi is most polluted city in the world in PM2.5 concentrations. 2  Half of the top 20 most polluted cities were in India, according to data.  PM2.5 is considered most harmful to health.
13 out of 20 cities on world's worst air pollution list are in India. CBC News Posted: Dec 08, 2015 12:53 PM ET Last Updated: Dec 10, 2015 11:28 AM ET. A woman wears a mask to protect herself from pollutants near Tiananmen Gate in Beijing on Dec. 1, 2015.